African Americans are more than 3 times as likely to progress to kidney failure as Caucasians and account for 32% of individuals with ESRD. Because of this, Indiana University School of Medicine researchers led by Jonathan Bazeley, MD, wanted to determine if serum phosphorus, which in previous studies of mainly Caucasian populations was associated with adverse outcomes in CKD patients, was an effective predictor in African Americans as well. African Americans and Caucasians differ in how they maintain balance of vitamin D and parathyroid hormone, which is why it was unknown if serum phosphorus levels would be an effective predictor in this population.